Manholes typically provide access, from the street level, to underground infrastructure, such as water mains, sewers or other utility networks. Manhole covers prevent pedestrians and vehicles from falling into the manholes, yet may be removed from covering the manholes when access is desired. Although typical unsecured manhole covers, which are formed from cast iron, can be somewhat difficult to pry open, those determined on gaining access to the manholes can overcome this difficulty.
In recent years, securing access to manholes has become a higher priority in order to block a potential avenue for terrorist attacks. A number of secure manhole cover designs have been proposed in the past, but there is still a need for improved manhole covers that include security devices, as well as the methods and apparatus for releasing and removing these secured covers from the manholes, for example, to provide legitimate access for the repair and maintenance of portions of the underground infrastructure.